Avaliação da produção de forragem de forrageiras estivais em resposta a estratégias de manejo.

O objetivo desse trabalho foi avaliar o comportamento da produção de forragem do capim-sudão BRS Estribo, do sorgo corte-pastejo (7.200) e de duas cultivares de Milheto (1.501 e 1.502) sob diferentes estratégias de manejo.Ana Cristina Mazzocato, editora técnica. ODS

Estudo da taxa de degradação de vitamina C em alguns sucos de frutas.

A vitamina C é uma vitamina de extrema importância para o ser humano não somente por sua atividade antiescorbútica, mas também pelas inúmeras atividades fisiológicas e antioxidantes que exerce. Este trabalho visa desmistificar o senso comum estabelecido de que a vitamina C é destruída pouco depois que um suco de frutas é preparado. Para isto, um breve estudo utilizando alguns sucos de frutas foi realizado. Tal estudo consistiu de extrações da vitamina C dos sucos preparados inicialmente e também após 2, 4 e 6 horas de exposição destes à temperatura ambiente. Os resultados obtidos mostraram que após seis horas o suco que obteve a maior perda de vitamina C foi o suco de laranja, mas tratou-se de perda inferior a 22% do teor inicial

Desempenho de novilhas Nelore e Nelore x Angus em sistema de Integração Lavoura-Pecuária da Embrapa Milho e Sorgo.

Evento online

Evolução da produtividade e produção de grãos no sistema de Integração Lavoura-Pecuária de corte da Embrapa Milho e Sorgo.

Evento online

Avaliação de processamento térmico de soja verde para consumo direto como hortaliça.

E-pôster 3339. CBCTA. 13 a 16 de agosto de 2018

Efficiency and residual effect of alternative potassium sources in grain crops.

ABSTRACT: The objective of this work was to evaluate the efficiency and the residual effects of both molten and ground alkaline potassium-silicate rocks (K1) and of ground phonolite rock (K2), as sources of potassium, compared with the traditional source (KCl), in grain crop successions. Two experiments ? one with the succession soybean-wheat-corn and the other with the succession corn-millet-soybean ? were conducted on a Typic Haplorthox in a randomized complete block design with four replicates. The treatments consisted of three sources (KCl, K1, and K2) and four rates of K (corresponding to 0, 0.5, 1.0, and 2.0 times the recommended rates for soybean and corn). The used sources did not affect leaf K concentration in soybean, but KCl and K2 similarly increased leaf K concentration in corn. Regardless of the source, K application increased the yield of all crops. The K1 and K2 sources present agronomic efficiencies equivalent to that of KCl. K1 and K2 show a more pronounced residual effect than KCl, especially on crops grown approximately one year after their application and under K rates above those recommended for the crops. Index terms: agronomic efficiency, phonolite, potassium fertilization, residual effect, rock dust, silicon. Eficiência e efeito residual de fontes alternativas de potássio em culturas graníferas RESUMO: O objetivo deste trabalho foi avaliar a eficiência e o efeito residual de rochas potássico-silicáticas alcalinas fundidas e moídas (K1) e de rocha de fonolito moída (K2), como fontes alternativas de potássio, em comparação à fonte tradicional (KCl), em sucessões de culturas graníferas. Dois experimentos ? um com sucessão soja-trigo-milho e outro com sucessão milho-milheto-soja ? foram conduzidos em Latossolo Vermelho argiloso, em delineamento de blocos ao acaso, com quatro repetições. Os tratamentos consistiram de três fontes (KCl, K1 e K2) e quatro doses de K (correspondentes a 0, 0,5, 1,0 e 2,0 vezes a dose recomendada para a cultura da soja e do milho). As fontes não afetaram a concentração de K nas folhas da soja, mas KCl e K2 aumentaram de forma semelhante a concentração de K nas folhas do milho. Independentemente da fonte, a aplicação de K aumentou as produtividades de todas as culturas. As fontes alternativas K1 e K2 apresentam eficiências agronômicas equivalentes à do KCl. K1 e K2 têm efeitos residuais mais pronunciados que o do KCl, especialmente em cultivos realizados aproximadamente um ano após suas aplicações e com doses de K acima das recomendadas para as culturas

Bird-spiders (Arachnida, Mygalomorphae) as perceived by the inhabitants of the village of Pedra Branca, Bahia State, Brazil

This paper deals with the conceptions, knowledge and attitudes of the inhabitants of the county of Pedra Branca, Bahia State, on mygalomorph spiders locally known as 'caranguejeiras' (bird-spiders). It is launched here a new filed within ethnozoology: ethnoarachnology, which is defined as the transdisciplinary study of the relationships between human beings and bird-spiders. Data were collected from February to June 2005 by means of open-ended interviews carried out with 30 individuals, which ages ranged from 13 to 86 years old. It was recorded some traditional knowledge regarding the following items: taxonomy, biology, habitat, ecology, seasonality, and behavior. Results show that bird-spiders are classified as "insects". The most commented aspect of the interaction between bird-spiders and inhabitants of Pedra Branca is related to their dangerousness, since they said these spiders are very venomous and can cause health problems. In general, the traditional zoological knowledge of Pedra Branca's inhabitants concerning these spiders is coherent with the academic knowledge

Effect of Elephant Grass Genotypes to Bioenergy Production.

The study aimed to evaluate the agronomic characteristics of elephant grass (Pennisetum purpureum Schum.) genotypes on energy production in the combustion form. A randomized block design with 3 repetitions was used. The treatments were arranged in subdivided plots scheme, considering as a plot the genotypes and as subplots, the harvest season. The agronomic characteristics plant height (H), leaf length (LL), leaf blade width (LBW), stem diameter (SD), tillers number (TN), stem percentage (SP), dry matter yield (DMY) were evaluated. The rainy season provided greater H to elephant grass genotypes with height above 3.5 m. The average SP obtained by the genotypes was 68.21% and 67.21% to the first and second year of cultivation, respectively, which gives the biomass good quality of burning. The rainy season provided greater DMY comparing to the dry season. In the first year of cultivation there were genotypes with annual dry matter yield (ADMY) above 50 ton ha-1 year-1, however, the non-maintenance of soil fertility promoted the reduction of 39.17% and 39.05% in the DMY and ADMY, respectively. Analyzing the agronomic characteristics, we conclude that the promising genotypes of elephant grass to produce energy in the form of direct combustion are CNPGL 91-25-1, Cubano Pinda, BRS Canará, Porto Rico and Mercker

The use of mulch in cultivating the forage cactus optimizesyield in less time and increases the water use efficiency ofthe crop.

Measurements of crop evapotranspiration (ETC) and crop coefficients (kC)incactus have not yet been adjusted for the phenological stage using conserva-tion practices (i.e. mulching). In this study, soil water dynamics, ETCandkCwere measured in the forage cactus under cultivation systems with (WM) andwithout (NM) the use of mulch in the semi-arid region of Brazil.Opuntiastrictawas subjected to irrigation depths based on a percentage of the referenceevapotranspiration (ET0) (rainfed, 25, 50, 75 and 100%) and to two systems ofcultivation: WM and NM. Over time, the phenophases (?Ph) were established;the soil water balance components were calculated and the crop yield wasevaluated at harvest. The use of 8.2 Mg ha1mulch led to almost no reducedwater consumption by the crop when compared to the NM system; however,the mulch did maximize yield, at 839C day, when irrigated with 50% ET0. ThekCvalue was higher under the WM system, with the differences decreasingthroughout the cycle (?PhI, 36%;?PhII, 27%;?PhIII, 23%;?PhIV-HT, 17%; and?PhIV-RF, 14%). Therefore, the use of mulch in cultivating the cactus opti-mized forage production in less time and significantly increased the water useefficiency of the cro